In the telecommunications industry telephone cable is introduced to multi-line customers at a single location or junction. An end of a multiple-conductor cable is prepared for ends of the respective discrete cables to be manipulated for interconnection with ends of respective discrete cables of the customer in an organized array by a multi-site distribution block or module. The module defines individual cross-connection sites wherein discrete terminals are housed within insulative housing sections, in a manner permitting ends of wires to be inserted into apertures of the housing sections to be electrically connected to the terminals. Each telecommunications cable conventionally contains a pair of conductors, termed tip and ring wires of a twisted pair cable, and the tip wire of each customer's cable must be connected to the tip wire of the respective distribution cable for each customer line, as well as the customer cable ring wire connected to the ring wire of the distribution cable; each cross-connection site contains a pair of terminals individually housed adjacent each other for convenience, with each terminal dedicated to one of the tip wire or ring wire of the wire pair. Preferably the connections of the wire conductors to the terminals is mechanical rather than soldered, and is separable to permit easy servicing or reprogramming involving disconnection and either reconnection or replacement of at least the customer wires.
One such multi-wire cross-connection module is disclosed in U.S. Pat. No. 4,431,247 shown to provide for cross-connection of up to twenty-five lines using fifty separately-housed terminals arrayed in five rows and ten columns secured in housing sections joined to a common base. Pads are provided at ends of the base for supporting and arranging individual wires or bundles of wires that are to be connected, and the base is adapted to be mounted to a support within a cabinet. Ends of the distribution cable conductors are electrically connected to the respective terminals beneath the horizontal base during (or even before) initial installation of the module in the cabinet, while ends of the customer cable wires are to be later connected to upper ends of the terminals in cylindrical housing sections or silos above the base. Connection of each of the customer cable wires is accomplished by insertion of the still-insulated wire end into an aperture of a respective housing section and through the housing section to extend beyond the far side, with portions of the wire extending through apertures of the terminal. An insulative cap member secured around the housing section is then rotated in a manner that presses the wire into a lateral slot of the terminal adjacent the insertion aperture while shearing off the free end portion of the wire extending beyond the wire exit aperture. An opening into the top of the cap permits insertion of a test probe engageable with a horizontally oriented contact tab to provide testing for assurance of a successful cross-connection.
Another approach to multi-cable cross-connection modules is disclosed in U.S. Pat. No. 4,210,105 wherein an insulated wire end section is pressed downwardly into vertical slots of the terminal and its free end trimmed, after which a screw member is threaded into the terminal to secure the wire in position. Other earlier approaches include wrapping of stripped wire ends about binding posts.
U.S. Pat. No. 5,006,077 discloses a terminal block having housing sections for a plurality of terminals for interconnecting pairs of wires. Two terminal members cooperate for terminating a customer cable conductor to a distribution cable conductor, with one of the terminal members being stationary while the other is in electrical engagement therewith and is rotated by an actuator after an insulated wire end has been inserted into an aperture of the housing section and through opposed openings of the rotatable terminal member until the wire free end reaches a stop within the housing section. Rotation of the rotatable member causes edges of at least one lateral slot of the terminal to be urged into engagement with the insulated wire to penetrate the insulation to establish assured electrical connection with the conductor of the wire. With smaller diameter wire, the wire extends completely through a center post of the housing section within the barrel-shaped terminal and slightly beyond the opposed side of the terminal remote from the wire entry aperture so that facing edges bounding a smaller dimension lateral slot penetrate the insulation to establish electrical connection, while edges along a larger dimension slot proximate the wire entry aperture merely compress the wire insulation to define a strain relief. The arrangement is shown to provide for a pair of wires to be so terminated and connected to an associated conductor of a stub cable beneath the terminal block that extends elsewhere for connection to the distribution cable.
In U.S. Pat. No. 5,219,302 is disclosed a cross-connect module in which a pair of terminals are housed in respective silos for termination to tip wires and ring wires of an individual customer cable to a distribution cable, with the terminals being rotatable for termination to insulated wire ends similarly to the disclosure of U.S. Pat. No. 5,006,077.
It is desired to provide a cross-connection system for cross-connecting an array of customer cables to a distribution cable at a common location, in a system that permits connection of alternate wires to the stationary terminal and thus to the distribution cable, after the primary wires of the customer cables have been installed and in service, in order to provide uninterrupted transmission service to the customer during repairing or servicing of the junction that requires temporary disconnection of the primary customer cable wires.
It is also desired to provide increased wire management area to the cross-connection array, providing greater clearance for placement of the wires within the array among the silos and from the respective cross-connection sites to the wire management fins at ends of the rack, while maintaining the existing spacing between the cross-connection sites.
It is further desired to provide for such cross-connection arrays to be spaced closely together.